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Offline Rickjames

CVT Tuning
« on: January 14, 2023, 01:09:12 PM »
CVT Tuning General Rules

Here are some general clutching rules you should play by!

Primary clutch (Drive Clutch) = Front clutch off the motor

Secondary Clutch (Driven Clutch) = Rear clutch connected to drivetrain

Peak RPM = The RPM the machine sits and holds most of the time at WOT. This needs to be in your model's peak powerband for best results. (BMP supplies you with your optimum peak RPM when purchasing clutch kits)

More Primary Clutch Weight = Less peak RPM & greater belt squeezing force

Less Primary Clutch Weight = More Peak RPM & less belt squeezing force

Primary Spring Starting Rate = Controls Engagement

Stiffer Primary Spring Starting Rate = Higher engagement RPM

Softer Primary Spring Stating Rate = Lower engagement RPM

Primary Spring Ending Rate = Controls Up Shift, Back Shift & Peak RPM

Stiffer Primary Spring Ending Rate = Slower Upshift, Quicker Backshift, More Peak RPM

Softer Primary Spring Ending Rate = Faster Upshift, Slower Backshift, Less Peak RPM

Steeper Helix Angle = Faster Upshift, Slower Backshift

Shallower Helix Angle = Slower Upshift, Faster Backshift

Stiffer Secondary Spring Finish Rate = Slower Upshift, Faster Backshift

Softer Secondary Spring Finish Rate = Faster Upshift, Slower Backshift

Adding horsepower normally means you need to add clutch weight, go steeper on the helix angle, or both. Most small modifications only require adding clutch weight while larger horsepower modifications will require you to change both.  Not changing clutching when you add horsepower will result in over-revving

Just something I found on the internet after hours of googling.
Uforce 600 2022

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Offline Lazydayz

Re: CVT Tuning
« Reply #1 on: January 14, 2023, 01:57:48 PM »
Good stuff
Nice an simple
21 uforce 1000
SA doors
30” dirt commander 2.0 on itp deltas
Custom cab and box cover
Custom clutching

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Offline Oifvet05

Re: CVT Tuning
« Reply #2 on: May 24, 2023, 02:08:58 PM »
Does anyone know the secondary spring rates? EPI makes a couple different secondary springs, it would help to know what we got.
2023 Uforce 600
bone stock so far

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Offline Oifvet05

Re: CVT Tuning
« Reply #3 on: May 24, 2023, 03:38:56 PM »
Got some info from EPI.

They recommended the Red SZ12 81.5 kg 104.3 kg or 176/212 at 3.5/2.5 in compressed heights

The factory spring is a 164/198 at 3.5/2.5 in compressed heights

EPI Spring is only $30, it would be worth a try
2023 Uforce 600
bone stock so far